BRA#2 peptide–Human Leukocyte Antigen-B*07:02 complex (BRA#2–HLA-B*07:02)

The BRA#2 peptide–Human Leukocyte Antigen-B*07:02 complex (BRA#2–HLA-B*07:02) is a specific molecular target consisting of a peptide derived from the C19orf48 protein presented by the HLA-B*07:02 class I molecule (Brickner et al., 2001, Journal of Experimental Medicine). This complex functions as a minor histocompatibility antigen (mHAg), which is a polymorphic peptide that can trigger T-cell responses in the context of allogeneic hematopoietic stem cell transplantation (HCT) (Goulmy, 1997, Current Opinion in Immunology). Because the expression of the BRA#2 peptide is largely restricted to hematopoietic cells and various leukemia cells, it serves as an attractive target for immunotherapy, particularly for inducing a graft-versus-leukemia (GvL) effect without causing widespread graft-versus-host disease (GvHD) (Kloosterboer et al., 2005, Biology of Blood and Marrow Transplantation). Therapeutic strategies targeting this complex include the development of T-cell receptor (TCR)-engineered T cells and TCR-like antibodies designed to recognize the specific peptide-MHC configuration (Heemskerk et al., 2007, Leukemia). Clinical interest focuses on treating hematological malignancies such as acute myeloid leukemia (AML) and chronic myeloid leukemia (CML) in HLA-matched, antigen-mismatched transplant settings.

Other names

Minor histocompatibility antigen BRA#2C19orf48-derived peptideBRA2 antigenBRA#2-HLA complexmHAg BRA#2

T-cell receptor (TCR) mediated recognition of the BRA#2 peptide presented by HLA-B*07:02, inducing cytotoxic T-lymphocyte (CTL) activity against leukemia cells.